/Engine/Source/Runtime/Slate/Public/Framework/Application/SlateApplication.h
Sets keyboard focus to the specified widget. The widget must be allowed to receive keyboard focus.
true if the widget is now focused, false otherwise.
virtual bool SetKeyboardFocus ( const [FWidgetPath](API\Runtime\SlateCore\Layout\FWidgetPath) & InFocusPath, const EFocusCause InCause )